2nd gen with ls1 a/c questions

[joeljet]

73 firebird with air already. want to use stock controls (can send out for modification) the opinion of any builders who have experience with more than one brand of aftermarket systems would probably help many on this forum.
question 1: who makes a bracket to install a sanden compressor in the stock ls1 position?

question 2: who makes the better system? vintage air, classic auto air, hot rod air, old air? or are there others?

question 3: should i just upgrade my old stuff? what need upgrading?

question 4: old air makes a heater control valve that recircs the water back to the water pump when the heater is not being used (which the ls1 needs), but its plastic. does anyone make a metal one?
thanx joel